A grand jury is expected to hear evidence concerning a lobbying effort involving former White House national security adviser Michael Flynn's work for the Turkish government, even as Flynn’s role in the special counsel’s investigation winds down New York Times reported citing people familiar with the inquiry.

The grand jury in Virginia will likely hear evidence that Flynn was serving as an unregistered agent of the Turkish AKP government in the US days after the 2016 election, the report said.

Robert S. Mueller III, the special counsel, had been handling the case and at some point referred it back to prosecutors in Alexandria, Va., who had originally opened the investigation, the people told the paper. According to the NYT, a veteran national security prosecutor is overseeing the case, and a grand jury has been empanelled to hear evidence.

Prosecutors for Mueller are examining Flynn’s former business partners and clients who financed a campaign against US-based Islamic preacher, Fethullah Gülen. He had been a close ally of Turkish President Recep Tayyip Erdoğan's AKP government. Gülen's network, which is also an Islamic cult, helping Erdoğan to redesign and install his Islamic-rooted AKP party in power in 2002. But his alliance with Erdoğan has faltered in recent years. CIA-related Gülen network attempted to topple down Erdoğan by a military coup in July 2016, but it failed.

Erdoğan has long demanded that Washington extradite Gülen.

The Trump White House recently asked federal law enforcement agencies to look into legal ways to remove Gülen from the US in attempt to ease Erdoğan’s pressure after Saudi Arabia's murder of Jamal Khashoggi at the Saudi consulate in Istanbul.

News of a grand jury's examination of Flynn's lobbying work comes a day after prosecutors with Mueller's special counsel investigation recommended that Flynn serve no jail time for lying to investigators, citing his contributions to their investigations.

Flynn did not register with the US authorities for his 2016 work for Turkish government, as is required by law, until almost a month after he was fired as Donald Trump’s national security adviser in February 2017. The office of Mueller in a memorandum filed with the court filing confirms that Flynn and his company were paid $530,000 for the work, which ended after Trump won the election in November.

Flynn admitted to prosecutors last year that he had repeatedly violated that law.

In 2017, Flynn and his business partner, Bijan Kian, filed additional lobbying disclosures acknowledging that the Gülen project "could be construed to have principally benefited the Republic of Turkey." They detailed payments to roughly a dozen other people and firms associated with the Gülen project.

Prosecutors could also be investigating reports that Flynn discussed kidnapping the cleric as part of a plan to forcibly return him to Turkey.